Intermittent resonance of the pyrolyzer induced draft fan
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The induced draft fan of the pyrolysis furnace has been in operation for 8 years. In previous years, there was a slight humming sound during operation, with no abnormal vibration levels. In recent years, the humming sound has gradually intensified, and the vibration levels of the bearings have increased sharply. Replacing the bearings yesterday did not resolve the issue. The buzzing doesn’t occur every 3 seconds. The fan base is fixed to the composite shock absorber. Has anyone had a similar experience?
Has the impeller been checked? Are there any impurities accumulated?
Has the part outside the pump body been checked? Is the pipeline unobstructed, are there any leaks, and what’s the condition of the fittings?
Clean the deposits from the impeller, check for any damage or blockages in the piping system, address abnormal noises that occur at regular intervals – these are often due to resonance from other equipment. Also, check whether the shock absorbers are worn out; if there has been a long period of downtime, it’s necessary to examine the concentricity of the main shaft.
Are shock absorbers installed at the bottom of the fan?
Furnace fans are usually installed on the steel structure of the air tank platform; as a result, the support system for the rotor is quite fragile. It is possible to try adjusting the springs in the fan foundation, or to determine the fault spectrum by measuring peak energy levels in real time. We also encountered significant vibration problems in the past, and improvements were achieved after strengthening the fan foundation and having the rotor balanced by external specialists! Also, the flue gas temperature of the furnace is relatively high, so the thermal expansion of the rotor must be taken into account!
The foundation of the pyrolyzer is prone to vibration. We have an actuator whose screws have all loosened.
The noise might be caused by damage to the bearing of the exhaust fan motor; it is not necessarily due to the fan’s bearings. I encountered this issue before; it was using motors from Jiamusi. After replacing the parts, everything worked normally again.
Check the coupling alignment; perform alignment at low temperature. Inspect and replace the bearings, ensuring that the clearances meet the standards. Clean any scale buildup on the impeller; it is advisable to replace it with a new one. Perform dynamic balancing of the rotor